The bold answer is incorrect. what is the right answer?

Last week, Mrs. Thomas, the AP Statistics teacher at Green Valley High School, gave her students an assessment on material they

blondinia [14]

Answer:

$0.88=\frac{X-83.54}{11.21}$

And if we solve for th value of X we got:

$X=83.54 + 0.88*11.21=93.405$

So then the score for Andrew is 93.405.

We need to take in count that the first quarter accumulates 0.25 of the area on the left, the second quarter 0.5, the third 0.75 and the fourth 1.0 of the area on the left. Based on the value obtained for the probability of 0.811 we see that we are on the last quarter of the distribution or the fourth quarter.

Step-by-step explanation:

1) Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

2) Solution to the problem

Let X the random variable that represent the scores of a population, and for this case we know the distribution for X is given by:

$X \sim N(83.54,11.21)$

Where $\mu=83.54$ and $\sigma=11.21$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we use the formula we got:

$0.88=\frac{X-83.54}{11.21}$

And if we solve for th value of X we got:

$X=83.54 + 0.88*11.21=93.405$

So then the score for Andrew is 93.405.

In order to find on which quarter is the score we just need to find this probability:

$P(Z$

We need to take in count that the first quarter accumulates 0.25 of the area on the left, the second quarter 0.5, the third 0.75 and the fourth 1.0 of the area on the left. Based on the value obtained for the probability of 0.811 we see that we are on the last quarter of the distribution or the fourth quarter.

7 0

4 years ago

Ms. Li spent $840 on a vacation. She spent 2/3 of the amount on a plane ticket and 1/2 of the remaining amount on food. How much

olya-2409 [2.1K]

$\bf 840\cdot \cfrac{2}{3}\impliedby \textit{on the plane ticket}
\\\\\\
\left( 840\cdot \cfrac{2}{3} \right)\cdot \cfrac{1}{2}\impliedby \textit{ on food}$

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When you bundle ten tens together they make 100, or a hundred

Ket [755]

100 is your answer!!!!!!

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joja [24]

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Find the equation of the plane passing through the points

erica [24]

Extract the normal vectors from the given planes:

$-2x+y+z+2=0\implies\vec n_1=(-2,1,1)$

$x+y-3z+1=0\implies\vec n_2=(1,1,-3)$

(which are unique up to their signs, meaning either $\vec n_1$ or $-\vec n_1$ are valid choices for the normal vector)

The third plane must be perpendicular to both these given planes, which means it would be parallel to both $\vec n_1$ and $\vec n_2$ , which in turn means its own normal vector $\vec n_3$ should be perpendicular to both $\vec n_1$ and $\vec n_2$ .